What’s scarier than a nine-foot great white shark? (This is not the set-up to a joke.)

How about something big enough – and presumably angry enough – to eat a nine-foot great white shark?

The Smithsonian Channel repackaged an Australian documentary called The Search for the Ocean’s Super Predator into another doc called Hunt for the Super Predator. The clip above comes from a particularly upsetting segment, picked up by the folks at Gizmodo.

The clip follows scientists attempting to catalogue Australia’s great white population. In particular, they are tracking a certain 9-foot great white, tagged just four months earlier. They found the shark’s “black box” on a beach, and the data seemed to indicate that the shark was eaten. But by what? (Cue music.)

They end up coming to the terrifying hypothesis that a “colossal cannibal great white shark” – estimated at 16 feet long and over 2 tons – snacked on his lil’ buddy. The scientists offer several suggestions as to how this nightmare become reality: Perhaps this was a territorial dispute, or maybe the larger shark was so hungry it was driven to attack another of its own species.